Disk drives are widely used in computers and data processing systems for storing information in digital form. In conventional Winchester disk drives, a transducer head "flies" upon an air cushion in very close proximity to a storage surface of a rotating data storage disk. The storage surface includes multiple magnetic storage domains that may be recorded and read back by the transducer head. The transducer head is supported near the storage surface using an actuator arm which is moved with an actuator motor.
The air cushion which enables the transducer head to fly in close proximity to the storage surface is created by air flow during rotation of the disk. When the disk rotation ceases, the air cushion dissipates and the transducer head is no longer supported above the storage surface of the disk. Thus, the transducer head "rests" or "lands" on the storage surface during non-rotation of the storage disk.
FIG. 1A illustrates a top plan view of a prior art disk drive 100 mounted to a frame 102 of a computer. FIGS. 1B and 1C illustrate a bottom perspective view of the prior art disk drive 100 during bending caused by a shock transferred to the disk drive 100. The bending illustrated in FIGS. 1B and 1C is exaggerated for clarity. In the prior art embodiment, the disk drive 100 includes a drive housing 104 having a base 106 and four, spaced apart threaded apertures 108. A bolt (not shown) is threaded into each of the threaded apertures 108 to secure the drive housing 100 to the frame 102.
Unfortunately, the threaded apertures 108, pursuant to disk drive industry standards, are asymmetrically located on the drive housing 104. As illustrated in FIGS. 1B and 1C, this unbalanced mounting scheme causes the drive housing 104 to bend and flex along a housing flex line 110 when the frame 102 is subjected to a shock impulse. Stated another way, because all of the threaded apertures 108 are asymmetrically located, a portion of the drive housing 104 cantilevers and flexes on the housing flex line 110 somewhat similar to a diving board.
Referring back to FIG. 1A, a disk assembly 112 is mounted on one side of the flex line 110 while an actuator assembly 114, including actuator arms 116 are attached to the base 106 on the other side of the flex line 110. As a result thereof, flexing of the drive housing 104 causes movement of the actuator assembly 114 relative to the disk assembly 112. Unfortunately, the movement to the actuator assembly 114 is amplified by the long, cantilevering actuator arms 116. This can cause the transducer heads 118 attached to the distal ends of the actuator arms 116 to lift off of the storage disk 120 and subsequently slam or slap back into the storage disk 120. This is commonly referred to as "head slap" in the industry. Head slap can lead to loss of data due to erosion or scarring of the magnetic film on the storage disk 120, debris particles in the disk assembly 112, as well as damage to the transducer heads 118.
One attempt to solve the problem includes isolating the entire disk drive by using four, soft shock absorbing mounts to mount the drive housing to the frame. The soft mounts are effective in protecting the disk drive from shock. Unfortunately, the soft mounts require more physical space than rigid mounts to implement. Further, the performance level of the disk drive is reduced because of the compliant nature of the soft mounts. More specifically, the soft mounts give during movement by the actuator motor and decrease the performance of actuator motor.
Other attempts include resonance tuning of the disk drive and mechanisms to prevent the liftoff of the transducer heads from the storage disks when the disks are not rotating. However, these attempts have proved to not be entirely satisfactory.
In light of the above, it is an object of the present invention to provide a device and method for reducing the effects of shock pulses to a disk drive. Yet another object of the present invention is to provide a mounting assembly for a disk drive which conforms to industry standards and which is relatively easy to manufacture and assemble. Still another object of the present invention is to provide a device or method which minimizes head slap and damage to the storage disk and/or the transducer head.